This investigation of DSM-III-R hypochondriasis and its treatment that were begun in the previous study. Some of the previous findings have generated new hypotheses about perception, cognition, and pathogenesis that merit testing. Other findings are definitive enough to form the basis of an intervention trial in which primary care physicians will be given a standardized psychiatric consultation about their hypochondriacal patients. To further elucidate the hypochondriac's amplifying cognitive and perceptual style, we propose an investigation of visceral perception, information processing, and past learning. It is hypothesized that hypochondriacs will display more accurate visceral interoception, and a cognitive style characterized by an attentional bias toward health- related cues and a tendency to consider ambiguous sensations pathological. Fifty DSM-III-R hypochondriacs and 50 controls will be accrued from a general medical clinic. They will complete the Structured Diagnostic Interview for Hypochondriasis (the criterion standard); self- report questionnaires and the heart beat discrimination test to measure somatosensory amplification; cognitive tests to assess attentional bias, symptoms attributions, and health beliefs; and a semi-structured interview to assess past learning about symptom appraisal and reporting. The prior study also identified a group of 35 patients with brief hypochondriasis associated with medical illness. A longitudinal follow- up of these patients is not proposed. They will be compared with 35 controls to determine whether they have an increased incidence of hypochondriasis and other major psychiatric disorder, and whether pre- existing somatosensory amplification is associated with subsequent chronicity. The same battery of questionnaire employed in the prior study will be repeated. Finally, 65 DSM-III-R hypochondriacs, accrued in the prior study, will serve as their own controls during a minimal intervention period, after which their physicians will receive a standardized written consultation on the management of hypochondriasis. Outcome variables include hypochondriacal symptoms, utilization of medical services, satisfaction with the physician and medical care, as well as physician attitudes and the concordance between patient and physician attitudes. These variables were measured in the prior study and will be repeated before and after the educational intervention.